is 18 too much?

[mike n]

i have a 2004 lund 12 foot aluminum boat.it is rated for a 10hp.i know that my 1957 18hp johnson is only a few more pounds than the 10hp but is it too much power?would it be dangerous or do damage to the transom?are these engines rated the same as todays engines?

mn

[frankr]

Weight is only a small factor. You are talking nearly twice the horsepower. Never mind the old how-it’s-rated arguement.

[20mercman]

Here is a photo of a Lund 14′ small hull that we run as high as a Mercury 200 on it. These are about the same weight as the 18 you are talking about, but the additional 2 feet is really important. This rig is at maximum with this motor on it.

I don’t remember what our Lund is rated for, but using the formula that’s been posted on here, I think I calculated it should be around 17-18hp., so I am not too far off. However like Frank said, in your case, that’s almost twice the rated power. We do have a 12′ Crestliner Commander 12 that is rated for 30hp, but with a Mk-25 on it, it is a real handful!

Steve

[amuller]

We have a 12 ft (actually closer to 11.5) cartopper. With a 5.5 Johnson is feels comfortable but has no speed. I’m getting ready to try a West Bend 12 hp on it but I think that will be pushing it. Point is, I agree that a couple more feet makes a difference. If I was doing this over I’d get a 14 footer which would give more flexibility in motors to use with it.

[20mercman]

Here is an underway photo of the same rig. Of course, this is far from WOT. This is pacing me in a 16′ Alumarine also with a 200 on it.

---

Attachments:

[PugetSoundBoater]

The boat length is a big factor. I have a 12′ Lund and i would not put anymore than a OMC 15 hp,cause its the same weight as a 9.9. I would also be very careful operating it,keeping the extra hp in mind.
On my 14′ Lund, i would be ok running a 20 hp as mercman shows,and i have done also with no problems, the length and boat weight make a big difference. Weight distribution is also a big factor. You most likely will need to move your gas tanks forward as far as possible, if you are the only person on board.

"Some people want to know how a watch works, others just want to know what time it is"
Robbie Robertson

[crosbyman]

if or when you exceed boat ratings and nothing happens it is not a problem ….

if something bad… happens all sorts of folks will be asking why you exceeded the boats rating put on there for a reason and any downstream liabilities will be yours to account for.

Insurance companies are quick to escape there responsibilities and dues when the risks are not within their plans coverage.

get a bigger boat if you need more speed… not just a motor

just mho

Joining AOMCI has priviledges 🙂

[garry-in-michigan]

I am the wrong person to ask about horse power limitations . . . 😆
9′ 4" LOA

10′ 9" LOA

You just have to be careful how you use that power . . . 😮

[dave-bernard]

If you have steering on it and not tiller it makes handling
much more comfortable

[Author]

Posts